carbon cycle

noun

Definition of carbon cycle

1 : the cycle of carbon in the earth's ecosystems in which carbon dioxide is fixed by photosynthetic organisms to form organic nutrients and is ultimately restored to the inorganic state (as by respiration, protoplasmic decay, or combustion)
2 : a cycle of thermonuclear reactions in which four hydrogen atoms synthesize into a helium atom by the catalytic action of carbon with the release of nuclear energy and which is held to be the source of most of the energy radiated by the sun and stars

Examples of carbon cycle in a Sentence

Recent Examples on the Web Researchers say the microbes represent an overlooked factor in efforts to balance Earth’s deep carbon cycle. Raleigh Mcelvery, Science | AAAS, 22 Apr. 2021 These scientists are all experts on forests, climate change, the carbon cycle and/or carbon removal. BostonGlobe.com, 10 May 2021 These scientists are all experts on forests, climate change, the carbon cycle and/or carbon removal. Lisa Song, And James Temple, ProPublica, 10 May 2021 The microbes appear to be playing an important role in the global carbon cycle by helping break down decaying plants without producing the greenhouse gas methane. Star Tribune, 26 Apr. 2021 But there is also a deeper carbon cycle, one that plays out over hundreds of millions of years. Raleigh Mcelvery, Science | AAAS, 22 Apr. 2021 Biology students may remember learning the water cycle, the carbon cycle or the nitrogen cycle. Alex Fox, Smithsonian Magazine, 15 Apr. 2021 The crackers are made from ingredients sourced from farmers who are using regenerative agricultural practices, which help improve the health of the soil and restore the natural carbon cycle. Meimei Fox, Forbes, 8 Apr. 2021 What if the legislative cycle were as sensitive and responsive as the carbon cycle? Jonathon Keats, Forbes, 10 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'carbon cycle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of carbon cycle

1901, in the meaning defined at sense 1

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Time Traveler for carbon cycle

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The first known use of carbon cycle was in 1901

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Statistics for carbon cycle

Last Updated

10 Jun 2021

Cite this Entry

“Carbon cycle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%20cycle. Accessed 19 Jun. 2021.

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More Definitions for carbon cycle

carbon cycle

noun

Medical Definition of carbon cycle

: the cycle of carbon in living beings in which carbon dioxide is fixed by photosynthesis to form organic nutrients and is ultimately restored to the inorganic state by respiration and protoplasmic decay

More from Merriam-Webster on carbon cycle

Britannica.com: Encyclopedia article about carbon cycle

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